/**
 * Copyright JS Foundation and other contributors, http://js.foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/

 /**
  * @mixin @node-red/runtime_flows
  */

/**
 * @typedef Flows
 * @type {object}
 * @property {string} rev - the flow revision identifier
 * @property {Array}  flows - the flow configuration, an array of node configuration objects
 */

/**
 * @typedef Flow
 * @type {object}
 * @property {string} id - the flow identifier
 * @property {string} label - a label for the flow
 * @property {Array}  nodes - an array of node configuration objects
 */

var runtime;
var Mutex = require('async-mutex').Mutex;
const mutex = new Mutex();

var api = module.exports = {
    init: function(_runtime) {
        runtime = _runtime;
    },
    /**
    * Gets the current flow configuration
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {Object} opts.req - the request to log (optional)
    * @return {Promise<Flows>} - the active flow configuration
    * @memberof @node-red/runtime_flows
    */
    getFlows: async function(opts) {
        runtime.log.audit({event: "flows.get"}, opts.req);
        return runtime.flows.getFlows();
    },
    /**
    * Sets the current flow configuration
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {Object} opts.flows - the flow configuration: `{flows: [..], credentials: {}}`
    * @param {Object} opts.deploymentType - the type of deployment - "full", "nodes", "flows", "reload"
    * @param {Object} opts.req - the request to log (optional)
    * @return {Promise<Flows>} - the active flow configuration
    * @memberof @node-red/runtime_flows
    */
    setFlows: async function(opts) {
        return mutex.runExclusive(async function() {
            var flows = opts.flows;
            var deploymentType = opts.deploymentType||"full";
            runtime.log.audit({event: "flows.set",type:deploymentType}, opts.req);

            var apiPromise;
            if (deploymentType === 'reload') {
                apiPromise = runtime.flows.loadFlows(true);
            } else {
                if (flows.hasOwnProperty('rev')) {
                    var currentVersion = runtime.flows.getFlows().rev;
                    if (currentVersion !== flows.rev) {
                        var err;
                        err = new Error();
                        err.code = "version_mismatch";
                        err.status = 409;
                        //TODO: log warning
                        throw err;
                    }
                }
                apiPromise = runtime.flows.setFlows(flows.flows,flows.credentials,deploymentType,null,null,opts.user);
            }
            return apiPromise.then(function(flowId) {
                return {rev:flowId};
            }).catch(function(err) {
                runtime.log.warn(runtime.log._("api.flows.error-"+(deploymentType === 'reload'?'reload':'save'),{message:err.message}));
                runtime.log.warn(err.stack);
                throw err
            });
        });
    },

    /**
    * Adds a flow configuration
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {Object} opts.flow - the flow to add
    * @param {Object} opts.req - the request to log (optional)
    * @return {Promise<String>} - the id of the added flow
    * @memberof @node-red/runtime_flows
    */
    addFlow: async function(opts) {
        return mutex.runExclusive(async function() {
            var flow = opts.flow;
            return runtime.flows.addFlow(flow, opts.user).then(function (id) {
                runtime.log.audit({event: "flow.add", id: id}, opts.req);
                return id;
            }).catch(function (err) {
                runtime.log.audit({
                    event: "flow.add",
                    error: err.code || "unexpected_error",
                    message: err.toString()
                }, opts.req);
                err.status = 400;
                throw err;
            })
        });
    },

    /**
    * Gets an individual flow configuration
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {Object} opts.id - the id of the flow to retrieve
    * @param {Object} opts.req - the request to log (optional)
    * @return {Promise<Flow>} - the active flow configuration
    * @memberof @node-red/runtime_flows
    */
    getFlow: async function(opts) {
        var flow = runtime.flows.getFlow(opts.id);
        if (flow) {
            runtime.log.audit({event: "flow.get",id:opts.id}, opts.req);
            return flow;
        } else {
            runtime.log.audit({event: "flow.get",id:opts.id,error:"not_found"}, opts.req);
            var err = new Error();
            err.code = "not_found";
            err.status = 404;
            throw err;
        }
    },
    /**
    * Updates an existing flow configuration
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {Object} opts.id - the id of the flow to update
    * @param {Object} opts.flow - the flow configuration
    * @param {Object} opts.req - the request to log (optional)
    * @return {Promise<String>} - the id of the updated flow
    * @memberof @node-red/runtime_flows
    */
    updateFlow: async function(opts) {
        return mutex.runExclusive(async function() {
            var flow = opts.flow;
            var id = opts.id;
            return runtime.flows.updateFlow(id, flow, opts.user).then(function () {
                runtime.log.audit({event: "flow.update", id: id}, opts.req);
                return id;
            }).catch(function (err) {
                if (err.code === 404) {
                    runtime.log.audit({event: "flow.update", id: id, error: "not_found"}, opts.req);
                    // TODO: this swap around of .code and .status isn't ideal
                    err.status = 404;
                    err.code = "not_found";
                } else {
                    runtime.log.audit({
                        event: "flow.update",
                        error: err.code || "unexpected_error",
                        message: err.toString()
                    }, opts.req);
                    err.status = 400;
                }
                throw err;
            })
        });
    },
    /**
    * Deletes a flow
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {Object} opts.id - the id of the flow to delete
    * @param {Object} opts.req - the request to log (optional)
    * @return {Promise} - resolves if successful
    * @memberof @node-red/runtime_flows
    */
    deleteFlow: async function(opts) {
        return mutex.runExclusive(function() {
            var id = opts.id;
            return runtime.flows.removeFlow(id, opts.user).then(function () {
                runtime.log.audit({event: "flow.remove", id: id}, opts.req);
                return;
            }).catch(function (err) {
                if (err.code === 404) {
                    runtime.log.audit({event: "flow.remove", id: id, error: "not_found"}, opts.req);
                    // TODO: this swap around of .code and .status isn't ideal
                    err.status = 404;
                    err.code = "not_found";
                } else {
                    runtime.log.audit({
                        event: "flow.remove",
                        id: id,
                        error: err.code || "unexpected_error",
                        message: err.toString()
                    }, opts.req);
                    err.status = 400;
                }
                throw err;
            });
        });
    },

    /**
    * Gets the safe credentials for a node
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {String} opts.type - the node type to return the credential information for
    * @param {String} opts.id - the node id
    * @param {Object} opts.req - the request to log (optional)
    * @return {Promise<Object>} - the safe credentials
    * @memberof @node-red/runtime_flows
    */
    getNodeCredentials: async function(opts) {
        runtime.log.audit({event: "credentials.get",type:opts.type,id:opts.id}, opts.req);
        var credentials = runtime.nodes.getCredentials(opts.id);
        if (!credentials) {
            return {};
        }
        var sendCredentials = {};
        var cred;
        if (/^subflow(:|$)/.test(opts.type) ||
            (opts.type === "tab") ||
            (opts.type === "group")) {
            for (cred in credentials) {
                if (credentials.hasOwnProperty(cred)) {
                    sendCredentials['has_'+cred] = credentials[cred] != null && credentials[cred] !== '';
                }
            }
        } else {
            var definition = runtime.nodes.getCredentialDefinition(opts.type) || {};
            for (cred in definition) {
                if (definition.hasOwnProperty(cred)) {
                    if (definition[cred].type == "password") {
                        var key = 'has_' + cred;
                        sendCredentials[key] = credentials[cred] != null && credentials[cred] !== '';
                        continue;
                    }
                    sendCredentials[cred] = credentials[cred] || '';
                }
            }
        }
        return sendCredentials;
    },
    /**
    * Gets running state of runtime flows
    * @param {Object} opts
    * @param {User} opts.user - the user calling the api
    * @param {Object} opts.req - the request to log (optional)
    * @return {{state:string, started:boolean}} - the current run state of the flows
    * @memberof @node-red/runtime_flows
    */
    getState: async function(opts) {
        runtime.log.audit({event: "flows.getState"}, opts.req);
        const result = {
            state: runtime.flows.state()
        }
        return result;
    },
    /**
    * Sets running state of runtime flows
    * @param {Object} opts
    * @param {Object} opts.req - the request to log (optional)
    * @param {User} opts.user - the user calling the api
    * @param {string} opts.state - the requested state. Valid values are "start" and "stop".
    * @return {Promise<Flow>} - the active flow configuration
    * @memberof @node-red/runtime_flows
    */
    setState: async function(opts) {
        opts = opts || {};
        const makeError = (error, errcode, statusCode) => {
            const message = typeof error == "object" ? error.message : error
            const err = typeof error == "object" ? error : new Error(message||"Unexpected Error")
            err.status = err.status || statusCode || 400;
            err.code = err.code || errcode || "unexpected_error"
            runtime.log.audit({
                event: "flows.setState",
                state: opts.state || "",
                error: errcode || "unexpected_error",
                message: err.code
            }, opts.req);
            return err
        }

        const getState = () => {
            return {
                state: runtime.flows.state()
            }
        }

        if(!runtime.settings.runtimeState || runtime.settings.runtimeState.enabled !== true) {
            throw (makeError("Method Not Allowed", "not_allowed", 405))
        }
        switch (opts.state) {
            case "start":
                try {
                    try {
                        runtime.settings.set('runtimeFlowState', opts.state);
                    } catch(err) {}
                    if (runtime.settings.safeMode) {
                        delete runtime.settings.safeMode
                    }
                    await runtime.flows.startFlows("full")
                    return getState()
                } catch (err) {
                    throw (makeError(err, err.code, 500))
                }
            case "stop":
                try {
                    try {
                        runtime.settings.set('runtimeFlowState', opts.state);
                    } catch(err) {}
                    await runtime.flows.stopFlows("full")
                    return getState()
                } catch (err) {
                    throw (makeError(err, err.code, 500))
                }
            default:
                throw (makeError(`Cannot change flows runtime state to '${opts.state}'}`, "invalid_run_state", 400))
        }
    },
}